What's the point?
...of Mr Tideman coming to see off Laskey, or to make sure he goes aboard Nimitz?
Presumably from the point of Owen's birth, there have been two of him on the planet at the same time, 40 years apart. The film infers it was Tideman/Owen's will to get Laskey on board but from Tideman's POV, it's all already happened once before without him being old Tideman and from Owen's POV, he doesn't even know who Laskey is.
Laskey's presence doesn't seem that key to the story. He suggests the possibility of time travel early on, but its the recce photos and Owen's knowledge that confirm it in the Captain's mind. Laskey doesn't change or alter any situation at all, its not even his idea that results in Owens being left in the past.